Washing drums of this type can be rotatably arranged in, for example, a washing machine for the washing of articles or in a tumble dryer for the drying of articles. More specifically, the said articles can be laundry, for example.
These washing drums need to be provided with an opening for the placement of the articles into the washing drum or the retrieval of the articles from of this washing drum. A problem herein is that this opening has to be able to be closed with a door, during the washing and/or drying, without this door being able to come open, upon rotation of the washing drum, under the influence of the centrifugal forces acting on this door. On the other hand, this door still has to be able to be easily opened and closed again.
In the type of washing drums to which the present invention relates, the opening for loading and unloading of the washing drum is provided in the casing and two door leaves are provided to close off this opening. These door leaves are provided with hooks and lugs in order to be able to hook together the door leaves. The door leaves have to be moved towards the inner side of the washing drum in order to be unhooked again and can afterwards be opened towards outside the drum.
In washing drums of this type, it is difficult to be able to reconcile the conflicting requirements of, on the one hand, being easily able to open and close these washing drums for the loading and unloading thereof and, on the other hand, preventing these washing drums from being able to be accidentally reopened during operation.
In domestic applications, a number of solutions have already been devised for keeping these washing drums more securely closed during operation thereof and for nevertheless being easily able to open and close these same for loading and unloading thereof. Similar washing drums which are more suited to domestic applications are known, for example, from FR 2 819 272 A1, FR 2 862 317 A1, FR 2 289 659 A1, FR 2 730 249 A1, DE 22 65 551 B1, DE 200 07 903 U1, EP 0 402 252 A1, EP 2 415 924 A1, EP 0 091 668 A1 and EP 2 381 025 A1. The washing drums which are herein described all comprise all of the characteristics from the introductory part of the first claim. In order to prevent the door leaves from being able to be unhooked during the washing, resilient elements, which in the closed position of the door leaves apply a spring force to the door leaves towards their open position, are provided. In order to unhook the door leaves, it is necessary to move the door leaves counter to this spring force in towards the inner side of the drum. These resilient elements also deliver to the door leaves the kinetic energy necessary to be more easily able to open a relatively heavy door leaf after having been unhooked.
The solutions which are herein used to reconcile the abovementioned conflicting requirements are insufficiently robust. however, to be able to be used in non-domestic applications.
The present invention relates more specifically—but not restrictively—to washing drums for use in non-domestic applications. By this are understood washing drums in which loads from 40 kg-50 kg to as much as 100 kg-300 kg are normal. In domestic applications, loads are generally limited to weights somewhere between 5 kg and 10 kg.
In heavier loads of this type, which are common in non-domestic applications, considerable centrifugal forces, which act on the door leaves, are generated during rotation of the washing drum. The solutions from the domestic applications for keeping the door leaves closed during rotation, and for nevertheless being easily able to open them, prove to be insufficiently robust given such considerable centrifugal forces. The used resilient elements cannot generally deliver the spring force necessary to be able to keep the door leaves sufficiently securely closed during operation. The rather fragile locking systems which are used in domestic applications in order to nevertheless be more easily able to open these door leaves are again in this case no match for such heavier centrifugal forces. In washing drums for non-domestic applications, a stronger locking mechanism for the door leaves, as described, for example, in DE 90 15 678 U1, is hence generally employed. A strong locking mechanism of this type ensures, however, that the opening of the door leaves is quite laborious. In washing drums of this type for non-domestic applications, it is also known to split the door leaves into parts which must be opened separately, side by side, in order to be able to unload the washing drum, and which must also be closed separately, side by side, before the washing drum can be set in operation. Here too, the opening and/or closing of the washing drum is quite laborious. The known solutions for non-domestic applications are consequently characterized by a quite laborious way of opening and closing the drum for the loading and unloading thereof.